With increase in base saturation, soil pH

Base saturation is the sum of the base cations held onto the soil exchange sites divided by the total CEC and expressed as a percentage. Base saturation is calculated as the percentage of CEC occupied by base cations.
Depending on soil pH, the soil's base saturation may be a fraction of CEC or approximately equal to CEC (Cation Exchange Capacity). With an increase in base saturation, soil pH increases.